Study On Preparation And Properties Of Y Zeolite Via Fly Ash

In recent years,fly ash production increased significantly with the increasedly use of coal.While,its various harm also received people's concern.So the comprehensive utilization of fly ash also has been a popular topic.Because of the total mass percent of SiO2 and Al2O3 in fly ash are similer with zeolite molecular sieve.Therefore,fly ash can be used to synthesis zeolites which have high purity.Y type zeolite not only has high adsorption quantity to H2O and CO2,but also effectively separate N2 and O2 in the air.It has high medical value.This study takes the fly ash from Shandong,China,as the raw material of synthetic Y type zeolite molecular sieve.The experiment use physical-chemical method,which is carbon thermal reduction-magnetic separation-acid pickling,to remove impurities.Morphologies and phase structures of the handled ash was characterized by means of XRD and SEM/EDS.Y type zeolite is synthesized by alkali melting-hydrothermal method.The experiment stuied the Y type zeolite molding process,performance testing of Y type zeolite and molding products.Morphologies and phase structures of the Y type zeolite was characterized by means of XRD?FT-IR?DSC-TGA.The results indicated that:(1)The best conditions for the reduction of fly ash is that:fly ash of 48 ?m,nc/no of 2.0,reaction occur in argon atmosphere,the reacting temperature is 1000 ? and reacting time is 1h.In the condition,the iron oxide was reduced for the iron and low state of iron,and calcium oxide has the least side effects.(2)The best conditions for the acid pickling of fly ash is that:mixing the fly ash of 48?m with 4mol/L hydrochloric acid with 3:1 solid-to-liquid ratio.The reacting temperature is 90 ?,and the time is 2h.After charactering with XRF,Si/Al ratio is 5.65,TFe content is 0.49%,and CaO content is 2.08%in the fly ash after removing impurities.(3)The best conditions for Y type zeolite molding process is that:the amount of sesbania powder dosage was 2%,CMC was 0.3%,nitric acid content was 8%,W/P ratio is 0.85.The molding zeolite must be dry at 110 ? for 2 h first,then be roasted at 550 ?for 2 h.The process must be controlled at 100 ?/h.The compressive strength is 9.68N/mm-1.(4)Through the adsorption test of Y type molecular sieve powder,the experiment indicated that:After being vacuumized for 30 min,CO2 and N2 adsorption quantity increase with the increase of pressure within a certain scope.The adsorption quantity independent is 13.56%and 11.3%in 0.1 MPa.But the O2 adsorption quantity does not change significantly and adsorption capacity is almost zero.(5)Through the static water adsorption test of Y type molecular sieve powder,the experiment indicated that:1h of vacuum pumping,35 ? in the oven for 24 h.The adsorption quantity is 17.62%.(6)Through the performance test of molding zeolite,the experiment indicated that:in the same condition,CMC had a slightly effect than others,in which the CO2 adsorption quantity was 11.63%,the N2 adsorption quantity was 10.31%,and the static water adsorption quantity was 15.71%.